| 摘要 |
A starter motor assembly is provided. A motor housing encloses an electric motor having a rotatable armature shaft. A planetary gear assembly is provided in a pinion housing, including planetary gears, a planet carrier, and a drive shaft. A pinion is engageable with the drive shaft for turning a flywheel of an engine. A non-load-bearing overrunning clutch assembly is provided, including an outer clutch piece removably fixed with respect to the pinion housing to be non-rotatable, and a rotatable inner clutch piece engaged with the planetary gears. Structure provided between the outer and inner clutch pieces allows rotation of the inner clutch piece in one direction and locks up the inner clutch piece in the other direction. When the starter motor assembly is energized, rotation of the armature shaft and planetary gears at a first rotational velocity rotates the inner clutch piece in the lockup direction. The inner clutch piece locks up, and the planetary gears race around the inner clutch piece and transmit rotation of the armature shaft to the drive shaft and the pinion to crank the engine. After the engine starts, rotation of the flywheel, drive shaft, and planetary gears at a second higher velocity rotates the inner clutch piece in the rotation direction, which absorbs the higher rotational velocity of the engine. The clutch assembly can be reversed inside the housing for use with either a clockwise-rotating motor or a counterclockwise-rotating motor. |
